Method of welding



y 7- w. c1 BUCKNAM ET AL 2,035,896

METHOD OF WELDING Original Filed April -e, 1929 2 Shepts-Sheei 1 v INVENTORS 2 .WORTHY C. BUCKNAM GEORGE I. JONES ATTORNEY y 1937. w. c. BUCKNAM ET AL 2,085,896

, METHOD OF WELDING I Original Filed April 6, 1929 2 Sheets-Sheet 2 I III/1153i IIIIIFAK A 24 1 28 I 27 WORTHY CBUCKNAM GEORGE l. JONES BY- I v 78 I5 $35- 3, mvswrons:

ATTORNEY Patented July 6. 1937 METHOD OF WELDING Worthy C. Bucknam, Mechanic Falls, Maine, and George I. Jones, Buffalo, N. Y., assignors, by mesne assignments, to Union Carbide and Carbon Corporation, a corporation of New York Original application April 6, 1929, Serial Nd. 353,129. Patent No. 1,947,755, dated February 20, 1934. Divided and this application June 28,

1933, Serial No. 677,994

10 Claims. (011113-112) Our invention relates to a method of welding in which'a flame is directed upon the puddle of weld metal at an inclination to the surface being welded and in the direction of the completed weld or rearwardly in respect to the progress of the weld.

An object of our invention is to efliciently fuse the' edges of the seam to be welded and to efiectively puddle the fused metal without blowing it out of the seam or burning'it. Another object of our invention is to reinforce the weld by blowing the fused puddle away from the direction of progress of the weld and above the surface of the metal being welded.

Our invention has special utility for welding longitudinal seams in tubes or plates by fusing the adjacent edges to be united and thereby causing the metal to-flow together and unite. The method can be conveniently performed with the use of a welding nozzle having a plurality of orifices supplied with a combustible gas such as oxygen and acetylene. The nozzle and the seam have a relative movement with respect to each other so that the flames formed by the combus tible gas issuing from the orificestraverse the seam in a lengthwise direction. Preferably the seam is progressively subjected to one or more preheating flames inclined in the direction of the movement of the flames with respect to the work and the seam is immediately subsequently subjected to one ormore flames inclined in the opposite direction to the movement of the flames with respect to the seam to fuse the edges of the seam ,into a puddle and complete the welding The above and other objects of our invention may be carried out by one or more forms of apparatus. For the purpose of illustrating our invention, it will be described in connection with the suitable form of apparatus disclosed in .the accompanying drawings, in which:

Figs. I, II, and III are respectively a sideview, a

plan view, and a rear end view of a torch nozzle;

Figs. IV, V and VI are sectional views on line IV-IV in Fig. II; line V--V in Fig. I; and line V'IVI in Fig. II, respectively.

Referring to the drawings, the torch head or nozzle comprises a nozzle block I of brass .or the like, having gas conducting and cooling fluid passages formed therein. A set of preheating nozzle tips 2, 3, 4 and 5, and a welding nozzle tip 6, project from the'bottom l of the nozzle block.

The tips are detachably coupled to the block andhave' gas passages communicating with the gas distributing passages therein. The preheating tips are attached to the upper step 'I-A and the welding tip is attached to the lower and downwardly extending step 'I-B formed in the bottom face of the block. The downwardly extending step 'IB makes it possible to place the lower end of the welding tip closer to the adjacent preheating tips for a given angle ofinclination of the welding tip included between;the rearwardly ,inclined welding tip and the bottom face of the nozzle block.

The top of the nozzle block I has a screw threaded gas inlet 8, adapted to be connec'ted to a mixing chamber 8A which supplies a combustible mixture of acetylene and oxygen or a like combustible gaseous mixture to the block. The

inlet 8 communicates with a longitudinal receiving chamber 9 formed in the block.

The receiving chamber communicates with a distributing chamber I0 underneath it. The'distributing chamber consists of a branch I I, parallel to the receiving chamber and a second branch I2, in communication with the first branch. The axis of the second branch is perpendicular to the axis of the first branch and in the same horizontal plane.

The first branch. II is provided with outlets I3 and I4, for supplying gas to the two forward preheating tips, and another outlet I5 for supplying gas to the welding tip. The opposite ends of the second branch I2 communicate with outlets I6 and II, for supplying gas to the preheating tips, 4 and 5, which are arranged at opposite sides of a vertical plane passing through the preheating tips 2, 3 and welding tip '6.

The receiving and distributing chambers are connected by a passage I8, which directs the gas into the distributing chamber against a wall thereof intermediate the outlet I4 and the branch I2. The chambers 9 and III are connected by another passage I9, which directs the gas into the distributing chamber at a point directly opposite the outlet I5, for supplying gas to the welding tip. The sum of the areas of passages I8 and I9 is made equal to or slightly greater than the sum of the areas of the gas passages in the nozzle tips in order to maintain a pressure within the chamber Ill suflicient 'to maintain the desired operating pressure and gas velocity within the nozzle tip passages.

For convenience the direction in which the arrow A in Fig. 1 points will be designated as a rearwardly direction and the arrow will also designate the relative movement of the work in respect to the torch, the shaft of the arrow being used to designate the surface of the work moving in the direction in which the arrow points. Forwardly inclined threaded sockets 20, 2|, 22 and 23 are formed in the bottom of the nozzle block below the respective outlets l3, l4, l6 and I! to receive threaded rear ends of the preheating nozzle tips. A rearwardly inclined threaded socket 24 is formed below the outlet IE to receive the welding tip. Each tip has a passage 25 therethrough which communicates with its respective outlet.

In this construction the preheating tips are forwardly inclined. The angle of inclination of these tips to the normal to the face of the block or the surface of the work is preferably about 10. The two forward tips 2 and 3 are in-line in reference to the line of movement of the work relative to the torch nozzle. The two intermediate tips 4 and 5 are located one on each side of the line of the first two tips. The welding tip 6 is inclined in a rearwardly direction and preferably at an angle of about to the normal to the face of the block or the surface of the work. This tip is in line with the two forward preheating tips. 7

A means is provided for cooling the torch nozzle to prevent it from becoming over-heated and to prevent a flash back from the gas due to the heat. Referring to Figs. I, II, and V, a U shaped cooling fluid passage 26, is shown formed in the block I. The two long branches of the U extend parallel to the gas receiving and distributing chambers and in a plane intermediate these chambers. Each branch of the U is provided with a hose, connection 21, one to supply the cooling fluid, and the other to discharge it. The several tips are made of copper or the like and, because of their mechanical connection to the block I, considerable heat is withdrawn from the tips by the water or other cooling medium that circulates through the block. The chambers and passages may be formed in the nozzle block in any convenient manner. As shown in the accompanying drawings they are drilled and the open ends of the holes are closed where necessary by plugs 28, 29, 30, 3| and 32.

In the operation of the torch nozzle, a. mixture of combustible gas is supplied from the mixing chamber 8A to the inlet 8, which delivers it to her the gas is broken up into as many streams as there are tips, a stream going to each tip.

Although our improved torch nozzle is especially useful on automatic welding machines which weld the longitudinal seams of tubular articles such as barrels, tanks and the like, it is also well adapted for use in weld uniting plates and similar work. It is generally preferable to mount the torch nozzle in a fixed position on the welding machine and feed the work so that the joint to be welded travels lengthwise under the nozzle along the main longitudinal plane of the preheating and welding flames. In some instances, however, the torch and improved nozzle may be propelled along the seam of stationary work to weld such seams. For convenience in explaining the operation of our improved nozzles, it will be assumed that the latter are stationary and the work seam is fed in the direction and along the line indicated by the arrow A in Fig. I.

The streams of gas issuing from the tips when ignited project flames upon the metal passing the ends of the tips. The seam to be welded is aligned with the bores 25 in the aligned tips 2, 3 and 6, and these tips direct a flame onto the seam, while the other two tips 4 and 5 direct a flame onto the metal surfaces adjacent each side of the seam. Considering one point on the seam of the metal as it advances under the tips, the flames from the preheating tips are successively directed upon this point in an inclined forwardly direction and the temperature of the metal is gradually increased thereby until the temperature has been brought substantially up to the fusion point of the metal when the point on the metal has passed the rearmost of the preheating tips. The flame from the welding tip is next directed upon this point in an inclined rearwardly direction. The metal is heated to or beyondthe temperature of fusion, and the edges of the metal are fused together.

Therfiorce of the rearwardly inclined welding flame pushes the fused metal to the rear of the welding tip where it may begin to cool instead of being pushed ahead of the tip and closer to the heating zone of the preheating tips and thus increase the tendency to burn the metal and blow it from the seam as is done in prior types of torch nozzles. produces an improved puddling of the fused metal and an improved weld is obtained.

A positive circulation of a cooling fluid in the passage 26 adjacent to the gas passages, keeps the torch nozzle cool, prevents flash backs, and generally increases the efliciency of the nozzle.

While we have described our invention in con-. nection with a certain type of apparatus, it will be understood that the degree of the inclination of the flames and other variations of our method may be made without departing from the scope of our invention as defined in the appended claims, it being essential however that the last flame directed upon the molten puddle be inclined rearwardly in respect to the progress of the weld.

This application is a division of our copending application, Serial No. 353,129, filed April 6,1929, which issued February 20, 1934 as Patent No. 1,947,755.

We claim:

1. The method of welding comprising heating the metal of the seam to be welded and directing a flame upon the puddle of weld metal at an inclination to the surface of the work and in the direction of the completed weld in order to impel the puddle of weld metal away from the direction of progress of the weld. I

2. The method of welding comprising progressively preheating the seam to be welded by pro- The rearwardly impinging flame gressively advancing a preheating flame along ing a forwardly inclined preheating flame on the" seam to be welded; and subsequently directing a rearwardly inclined welding flame on the same portion of the seam to be welded, said inclination being in respect to the surface of the work being welded and in respect to the direction of the progress of theweld, said rearwardly inclined welding flame serving to impel molten metal away-from the direction of progress of the weld.

4. The method of welding comprising progresprogressively advancing a forwardly inclined preheating flame alongthe seam; and simultaneously advancing a rearwardly inclined welding flame along the preheated surface, said inclination being in respect to the surface of the work being Welded and in respect to the direction of the progress of the weld, said rearwardly inclined welding flame serving to impel molten metal away from the direction of progress of theweld.

5. The method of welding a flat metal member, said method comprising heating the metal of the seam to be welded, and directing a flame upon the puddle of weld metal at an inclination to the surface of the work and in the direction of the completed weld.

6. The method of welding comprising directing a forwardly inclined preheating flame on the seam to be welded and subsequently directing a rearwardly inclined welding flame on the same portion of the seam to be welded, said preheating flame and said welding flame being moved together and being divergent from each other, and said inclination of each flame being in respect to the surface of the work being welded and in respect to the direction of the progress of the weld.

7. The method of welding a horizontal metallic seam which comprises the steps of heating the metal of the seam substantially to the fusion temperature by directing forwardly inclined flames upon said seam, and completing such Welding by further heating and propelling such metal away from the influence of said forwardly inclined flames by va rearwardly inclined flame whereby said seam is fused rearwardly of said rearwardly inclined flame.

. 8. A method of welding a seam in metal whichcomprises preheating successive portions along said seam, and applying a rearwardly inclined high-temperature flame to such preheated portions.

9. A method of welding a seam in metal work which comprises preheating successive unwelded portions of the work along said seam by apply: ing a preheating flame to such portions, and then applying a rearwardly inclined welding flame to such preheated portions.

10. A method of welding a seam between metal members which comprises preheating successive unwelded portions of said members along said seam by applying a forwardly inclined preheating flame to such portions during relative movement of said flame and .said members lengthwise of said seam, and applying a rear- I wardly inclined welding flame to such preheated portions during such relative movement.

WORTI-IY C. BUCKNAM. GEORGE I. JONES. 

